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A silicone rubber foam is prepared by introducing polydiborosiloxane (PDBS) into silicone rubber, and using expandable microspheres as blowing agents. The influences of the dual network structure with dynamic cross-linking network on the silicone rubber foam is characterized by the cell size, mechanical properties and impact resistance. The cell size increases from 77 to 93 [micro]m due to the introduction of a dynamic cross-linking network which reduces foaming resistance. The elongation at break elevates from 277% to 574%, and the yield strength gradually decreases. The dynamic cross-linking network also enhances the internal damping characteristic and energy absorption capacity of the foam. The impact resistance of silicone rubber foam is improved because of the synergistic effect of the dual network structure and the bubble structure. The research improves the performance of silicone rubber foam. KEYWORDS anti-impact, dynamic cross-linking, polydiborosiloxane, silicone rubber Highlights * The dual network structure to improve the mechanical properties. * Excellent cell is obtained using expandable microspheres as foaming agent. * The toughness and elongation are enhanced by regulating the molecular structure. * The dual network structure ameliorates the damping and energy absorption. * Dynamic cross-link and expandable microspheres increase the impact resistance., 1 | INTRODUCTION Silicone rubber as a polymer elastomer is extensively used in various field due to its excellent thermal stability, (1) mechanical property, (2) biocompatibility, and radiation resisting property. [...]

The development of digitization is soaring and has brought dividends to many industries in China. In this paper, the correlation between digitalization of corporate financial accounting management innovation and corporate performance of Chinese listed companies is explored through a regression model by taking the effect of digitalization of corporate financial accounting management and the time of implementation as the independent variables, and controlling the shareholding structure, corporate development capability, market price, and assets and liabilities as the control variables of the model. Further, based on heterogeneity analysis and robustness tests, we explored the impact of financial management digitization on corporate performance under different property rights. The conclusions we draw are further validated. The results show that the regression coefficient of digital innovation in accounting management and return on net worth is 0.0169, with a significant increase in return on net worth at the 10% level, and the substantial coefficient in digital innovation duration and firm performance is 0.00298, both of which have a considerable contribution. This study can not only promote enterprises to achieve cost reduction and efficiency, but also provide reference for enterprises to implement digital transformation, promote industrial digital transformation, and promote the development of the digital economy.

Stability is the most pressing challenge hindering the commercialization of perovskite solar cells (PSCs), and previous efforts focused more on enhancing the resistance of PSCs to external stimulus. Here, we found that the indium tin oxide (ITO) will deteriorate the photovoltaic performance of PSCs through positive feedback cycles. Specifically, the perovskite degradation products will cross the electron transport layer to chemically etch the electrode ITO to generate In3+, which will migrate upwards into the perovskite film. Then, the reaction that corrodes ITO consumes the decomposition products of perovskite and shifts the balance of the perovskite decomposition reaction, further promoting the degradation and thus falling into a positive feedback cycle. Moreover, the In3+ in the perovskite film was found to accumulate at the upper surface, which would lead to n‐type doping of perovskite film to form the energy barrier for interface carrier extraction. Subsequently, the chelating molecule ethylenediaminetetraacetic acid disodium salt (EDTA‐2Na) was introduced onto ITO to firmly chelate the In3+ and prevent it from migrating upward, thus breaking this internal positive feedback cycle and significantly enhancing the efficiency and stability of PSCs. This work provides new perspectives for understanding the mechanism of photovoltaic performance loss and ionic transport in PSCs. [ABSTRACT FROM AUTHOR]

In the quest to elevate the mechanical properties of cellulose nanofiber-reinforced poly (lactic acid) composite materials for robust industrial applications, we conducted multiscale nonlinear finite element analysis rooted in homogenization theory. Our study delved into the intricate web of mechanical mechanisms and their pivotal influencers. This paper zeroed in on three paramount factors: the distribution of fibers, the fiber–matrix interface, and the aspect ratio of the fibers. For fiber distribution, we assumed fiber orientation control in fused filament fabrication and clarified the limit of material improvement by setting one-dimensional orientation as the upper limit. Our analysis of the fiber–matrix interface proposed a comprehensive three-scale structure, encompassing microstructures featuring intricate interfacial phases around the fibers, sub-microstructures with myriad dispersed fibers, and macrostructures subjected to external loads. The profound impact of the fiber–matrix interface on material properties was unveiled through a meticulous two-step homogenization process. Furthermore, we examined the substantial influence of the fiber aspect ratio on material properties. By unraveling the complex interplay among these critical factors, this research provided new design guidelines for fiber morphology to the performance of cellulose composites. [ABSTRACT FROM AUTHOR]

A bipolar polymer cathode material, containing redox-active azo benzene and diamine moieties, was synthesized for sodium-ion batteries. The n-type azo group and p-type amine group enable a wide cutoff window with an initial capacity of 93 mA h g−1 at 50 mA g−1 and a high voltage plateau at ∼3.3 V. [ABSTRACT FROM AUTHOR]

Carbonate-based electrolytes, known for their high solvation energy and high ionic conductivity at room temperature, present significant challenges in ultra-low temperature and fast charging applications. In the February issue of Nature, Fan and colleagues demonstrated that utilizing solvents like fluoroacetonitrile with small molecular size and low solvation energy, facilitates the creation of rapid ion-conduction ligand channels and enables the formation of an inorganic-rich interphase for high-performance ionic batteries, effectively addressing the aforementioned challenges. [ABSTRACT FROM AUTHOR]

Precipitation hardening stainless steel (PHSS) possesses high strength, impact resistance, and corrosion resistance, making it extensively employed in aerospace, nuclear power equipment, and petrochemical industries. The precipitates and reversed austenite (RA) generated during heat treatment significantly influence the properties of PHSS. This study investigates the impact of aging temperature (480–620 °C) on PH 13-8Mo stainless steel. As the aging temperature increased from 480 °C to 620 °C, the yield strength (YS) and ultimate tensile strength (UTS) initially increased and then decreased, while the impact energy initially decreased and then increased. At an aging temperature of 510 °C, the strength and hardness reach their maximum values, indicating peak aging conditions. The microstructure after aging treatment is lath martensite, RA and NiAl. With increasing aging temperature, the size of NiAl precipitates increases, accompanied by a rise in RA content. The quantitative analysis assessed the contributions of various strengthening mechanisms (precipitation strengthening, solid solution strengthening, grain refinement strengthening, dislocation strengthening, etc.) to YS. Quantitative calculations revealed that the precipitation strengthening effect was most pronounced at an aging temperature of 510 °C. [ABSTRACT FROM AUTHOR]

Objective: Systematic evaluation of the safety of del Nido cardioplegia compared to cold blood cardioplegia in adult cardiac surgery. Methods: We systematically searched PubMed, EMbase, The Cochrane Library and ClinicalTrials.gov for randomized clinical trials (published by 14 January 2024) comparing del Nido cardioplegia to cold blood cardioplegia in adult. Our main endpoints were myocardial injury markers and clinical outcomes. We assessed pooled data by use of a random-effects model or a fixed-effects model. Results: A total of 10 studies were identified, incorporating 889 patients who received del Nido cardioplegia and 907 patients who received cold blood cardioplegia. The meta-analysis results showed that compared with the cold blood cardioplegia, the del Nido cardioplegia had less volume of cardioplegia, higher rate of spontaneous rhythm recovery after cross clamp release, lower levels of postoperative cardiac troponin T and creatinine kinase-myocardial band, all of which were statistically significant. However, there was no statistically significant difference in postoperative troponin I and postoperative left ventricular ejection fraction. The clinical outcomes including mechanical ventilation time, intensive care unit stay time, hospital stay time, postoperative stroke, postoperative new-onset atrial fibrillation, postoperative heart failure requiring intra-aortic balloon pump mechanical circulation support, and in-hospital mortality of both are comparable. Conclusion: Existing evidence suggests that del Nido cardioplegia reduced volume of cardioplegia administration and attempts of defibrillation. The superior postoperative results in CTnT and CK-MB may provide a direction for further research on improvement of the composition of cardioplegia. [ABSTRACT FROM AUTHOR]

Objective: To identify major contributors, current research status, and to forecast research trends and future development prospects on acupuncture and moxibustion therapy for herpes zoster (HZ) and postherpetic neuralgia (PHN). Methods: A systematic search was conducted on the China National Knowledge Infrastructure (CNKI), Weipu, WanFang databases, and the Web of Science Core Collection (WoSCC), PubMed, and Scopus databases. The search strategy included relevant terms for HZ, PHN, acupuncture, and moxibustion. The reference type was limited to articles or reviews, with a publication date from January 1, 2014 to December 31, 2023. Data analysis was performed using CiteSpace software, focusing on author, institution, source, and keyword distributions, and temporal trends. Results: A total of 1612 publications were identified from both Chinese and English databases. The analysis revealed a rising trend in publication numbers in the English database, with a significant increase observed in 2020. In the Chinese database, publication activity exhibited two peaks in 2019 and 2023. Guohua Lin and Jingchun Zeng were the most prolific authors in the Chinese and English databases, respectively. The Chengdu University of TCM and Zhejiang Chinese Medicine University were the most active institutions. The keyword analysis revealed "herpes zoster" as the most frequent keyword in the Chinese database, while "postherpetic neuralgia," "acupuncture," and "management" were prominent in the English database. The study also identified several therapeutic approaches, including fire needle therapy and electroacupuncture, which have shown efficacy in treating HZ and PHN. Animal studies provided insights into the mechanisms of these therapies, suggesting potential modulation of neuroinflammatory markers and intracellular signaling pathways. Conclusion: The bibliometric analysis underscores the growing interest in acupuncture and moxibustion therapy for HZ and PHN. It highlights the contributions of key authors and institutions while pinpointing potential areas for future research. The study advocates for the necessity of large‐scale, multi‐center clinical trials and further basic mechanical research to optimize these therapies. Moreover, it also emphasizes the importance of international collaboration to strengthen the evidence base and expand the global impact of this traditional treatment modality. [ABSTRACT FROM AUTHOR]

This paper introduces a conceptual framework for finite element analysis of generalized Maxwell viscoelastic materials based on the initial stress approach. The proposed method facilitates the explicit and convenient determination of mechanical parameters for viscoelastic materials by directly utilizing relaxation test data. Each time step's viscoelastic relaxation stress is treated as the initial stress, and a recursive calculation formula for the material's initial stress is established, relying solely on the relaxation stress and strain from the previous time step. Based on this, the study outlines the computational steps for initial-stress-based finite element analysis of elastic materials. The proposed algorithm's accuracy and efficiency are validated through a classical one-dimensional axial rod example. Results demonstrate that the introduced initial stress-type finite element analysis maintains the stiffness matrix equal to the initial stiffness matrix throughout the calculation process, significantly enhancing the efficiency of finite element analysis for viscoelastic materials while reducing the computational resource required. The conceptual framework improves the efficiency and accuracy of analyzing the mechanical parameters of viscoelastic materials using relaxation test data. [ABSTRACT FROM AUTHOR]

Background: This study aimed to explore the incidence of occult lymph node metastasis (OLM) in clinical T1 − 2N0M0 (cT1 − 2N0M0) small cell lung cancer (SCLC) patients and develop machine learning prediction models using preoperative intratumoral and peritumoral contrast-enhanced CT-based radiomic data. Methods: By conducting a retrospective analysis involving 242 eligible patients from 4 centeres, we determined the incidence of OLM in cT1 − 2N0M0 SCLC patients. For each lesion, two ROIs were defined using the gross tumour volume (GTV) and peritumoral volume 15 mm around the tumour (PTV). By extracting a comprehensive set of 1595 enhanced CT-based radiomic features individually from the GTV and PTV, five models were constucted and we rigorously evaluated the model performance using various metrics, including the area under the curve (AUC), accuracy, sensitivity, specificity, calibration curve, and decision curve analysis (DCA). For enhanced clinical applicability, we formulated a nomogram that integrates clinical parameters and the rad_score (GTV and PTV). Results: The initial investigation revealed a 33.9% OLM positivity rate in cT1 − 2N0M0 SCLC patients. Our combined model, which incorporates three radiomic features from the GTV and PTV, along with two clinical parameters (smoking status and shape), exhibited robust predictive capabilities. With a peak AUC value of 0.772 in the external validation cohort, the model outperformed the alternative models. The nomogram significantly enhanced diagnostic precision for radiologists and added substantial value to the clinical decision-making process for cT1 − 2N0M0 SCLC patients. Conclusions: The incidence of OLM in SCLC patients surpassed that in non-small cell lung cancer patients. The combined model demonstrated a notable generalization effect, effectively distinguishing between positive and negative OLMs in a noninvasive manner, thereby guiding individualized clinical decisions for patients with cT1 − 2N0M0 SCLC. [ABSTRACT FROM AUTHOR]

The marine shale within the Sichuan Basin constitutes China's significant shale gas production, featuring old formation age, high degree of thermal evolution, multiple tectonic movements, and complex structural conditions. However, there are significant differences in the shale gas preservation conditions and reservoir quality in different areas, limiting future large-scale exploration and development. Pore structure significantly influences shale reservoir quality, gas content, and exploration of shale gas occurrence, migration, and enrichment mechanisms. The influence of structural-dominated preservation conditions on shale pore structures is essential to comprehend for effective shale gas exploitation. This study employs field-emission scanning electron microscopy in conjunction with other techniques (low-temperature N2 adsorption, low-temperature CO2 adsorption, and nuclear magnetic resonance) for detailed analyses of the pore structure across varied structural zones, revealing the influence of structural attributes, fault systems, depth of burial, and formation pressure on pore architecture, and examining the relationship between pore structure and shale gas preservation conditions. The results show that stable structural condition is conducive to the development and preservation of shale pores. Structural compression causes inorganic and organic pores to become narrow and elongated due to shrinkage, with a significant increase in microfractures. The porosity of shale with stable structural conditions exhibits markedly increased porosity compared to samples under structural compressions. Under conditions of similar TOC and mineral composition, the pore size distribution (PSD), pore volume (PV), and specific surface area (SSA) of shale after structural compression are significantly lower than those of samples with stable structural conditions. As the burial depth increases, the shale porosity shows a decreasing trend, but the decrease is limited. Burial depth significantly impacts the SSA and PV of high-TOC samples (3%-6%). As the burial depth increases, both SSA and PV show a significant decreasing trend. When the burial depth reaches 4000 m, SSA and PV tend to concentrate. The formation pressure coefficient is an important factor for the development and preservation of shale pores, and porosity is positively correlated with the formation pressure coefficient. Increased formation pressure coefficient indicates superior preservation conditions and enhanced pore development. [ABSTRACT FROM AUTHOR]